With both incoming and outgoing calls via Skype-gateway sound quality is awful. Strong heartbeats and clicks are audible in a voice , the sound is intermittent. Quality is improving a bit if you use an old Skype version (5 or 4).

The sound is bad only with SIP to Skype and Skype to SIP calls.
The problem apparently exsists not in the Skype but in the gateway or PBX itself or between them. If I listen to the sound during this kind of calls and connect directly to the audio card jack with my headphones, I hear perfect quality.
Also I have the audio-card replaced and it did not help.

I think, everything is configured correctly and "voice through PBX" option is seleced.

I ask for your advice, I do not know how to find the reason of this issue and how to fix it.

Thank you.

leejor
My understanding, of the operation 3CX Skype gateway, is that it uses the sound

card "facilities", of the PC. Which I take it to mean that the conversations actually

convert from digital, to analogue, than back to digital. It is the analogue part, that is

probably causing the problem.

You say that you have replaced the audio card, but, are all other audio programmes

(surround sound/multi-speaker/audio enhancement), sort of options, also removed? Given

that the gateways does actually work on many installations, I have to assume (first

choice) that it is something to do with the audio hardware (or their settings) on your

particular computer.

Oleksandr said:

leejor,

Yes, I thougt about audio hardware issues first. Butat the same time (during the call) I

Click sounds, may be the result of dropped/missing packets. The audio portion will usually introduce distortion, over modulation, or a relatively steady background noise, so it may not be the audio card. Is there any sort of "bottleneck" possible in your network, or to/from your VoIP provider?

There is no "bottleneck" I could imagine. Everything goes thru localhost.
I turened off ativirus software and it did not help. I have replaced watchguard firewall with d-link router and it did not help.
I tried to replace the motherboard, I put new one from my spare parts - no result.

After some research I think this clicks are periodical delays in the flow or delays in encoding.

If I listen directly from skype the sound is clear.

Also it appears randomly. First call has usually almoust perfect sound and clicks are coming during the second call.

There is no "bottleneck" I could imagine. Everything goes thru localhost.

Click to expand...

So...you are using the 3Cx Phone and the 3CX PBX/Skype gateway all on the same PC??

Perhaps there is an audio conflict running the Skype gateway and the 3CX Phone simultaneously on the same machine (if that is the case).

Have you tried using the 3CX Phone, on another PC, or using a stand alone SIP phone/ATA?

The gateway does work, I use it on occasion, and while not always the best audio quality, it isn't noticeably worse that some VoIP calls I've made. I have to assume that it is a hardware, network, or software conflict somewhere in your set-up